Understanding and Respecting End-of-Life Treatment Preferences Among Older Adults with Alzheimer's Disease and Related Dementias Project Summary/Abstract Cognitive impairment is extremely common near the end of life. Cognitive impairment often co-occurs with physical health conditions and the clinical progression of dementia and other chronic conditions can lead to frequent hospitalizations and situations requiring decisions about aggressive and potentially burdensome treatments that are unlikely to improve the survival or quality of life for these patients. Because cognitive impairment frequently precludes these patients from participating in decisions about their care, surrogate decision-makers must often make decisions quickly and with limited information about their loved ones' preferences. Although advance directives have been associated with less aggressive care for cognitively impaired patients, only a minority of cognitively impaired older adults prepare these documents. Expanded use of advance care planning (ACP) is viewed as a potential way of improving the quality of end-of-life care, but a number of questions remain. It is unclear whether cognitive functioning influences treatment preferences, how surrogate decision makers view treatment options, how they use preference information, and whether framing of treatment choices influences surrogate decision-making. In this project, an interdisciplinary team including researchers with expertise in economics, health policy, bioethics, critical care, mental health and nursing addresses three aims. The first two analyze new and existing survey data collected among Health and Retirement Study respondents and decedents to 1- Test whether decision-maker characteristics and the presence of written or oral directions influence the decisions currently being made for persons with Alzheimer's disease and Alzheimer's disease Related Dementias (AD/ADRD); 2- Describe the relationships between cognitive impairment, end-of-life treatment preferences, and advance care planning (ACP). Informed by Aims 1 and 2, aim 3- Conduct online experiments to test how the choices that American adults think surrogate decision-makers should make for persons with AD/ADRD vary with characteristics of patients' preferences and advanced care planning. Findings from this study will address evidence gaps around advance care planning for AD/ADRD highlighted in the NIA/NINR Funding Opportunity ?Improving Quality of Care and Quality of Life for Persons with Alzheimer's Disease and Related Dementias at the End of Life,? and priorities articulated in the National Plan to Address Alzheimer's Disease. Results from this study can help to design interventions to increase the likelihood that a patient engaging in advance care planning has the conversations or prepares the documents that allow family, friends, and clinicians to act in a patient's best interest after dementia onset. Findings can also inform decision-making when ACP may no longer apply or was not completed.